The results were intriguing, despite the small number of study participants: five, two of whom were pregnant. Detailed information has not been available about immune responses against Zika in humans, especially T cell responses.

Highlights from Mulligan’s abstract:

*All five seemed to have a hole in their immune systems – functional antiviral “killer” CD8 T cells were rare, despite activation of CD8 T cells in general and strong responses from other cell types.

*”Even with prolonged maternal viremia, both pregnancies resulted in live births of apparently healthy babies.”Zika infection during pregnancy can cause birth defects affecting the fetal brain. The infection is often reported to be asymptomatic or have relatively mild symptoms, such as a rash, lasting around a week. The longer infection periods in the pregnant women (more than 44 days in one case) bear some similarity to reports of an extended period of Zika infection in pregnant rhesus macaques.